NUCLEAR TESTS

asked the Prime Minister what information he has received from the United States Administration on the recent leakage of radiation in Nevada after underground nuclear tests; if he will request the United States Administration, in the interests of the health of the peoples of the world, to refrain from conducting further underground tests until it is certain that there can be no further leakages; and if he will intensify his efforts to secure a complete ban on all such tests.

Can my right hon. Friend say whether his circulated Answer contains any reference to the previous radiation leak a few years ago, after tests for which the then British Government were partly responsible? Does he recall that we were then given assurances that it was unbelievable that there should be any such leakages again?

I would ask my right hon. Friend to study my Answer. There have been one or two cases in the United States, but none of them was in any sense a breach of the nuclear test ban. There was also one in the Soviet Union, due again, I am satisfied, to miscalculation and not to any attempt to circumvent the plan. All these have led to a small amount of venting, which all of us, and all countries, very much regret.

Will the Prime Minister make representations in the strongest terms to the Chinese People's Republic about the test which they have carried out in the atmosphere? These tests are infinitely worse than any underground test in the United States.

The hon. Member is absolutely right about this. The test carried out a few days ago—which, I gather, was about 130 kilotons—has undoubtedly involved a considerable amount of fall-out, although it may take a few days—perhaps up to a month—before it is possible to calculate exactly how much fall-out has occurred from this test, which is not a breach of the test ban agreement because China is not a member, but which is completely opposed to what the whole of mankind wants to see.

While we will continue to urge the Prime Minister to attempt to secure an overall ban on tests, can he confirm that there was no leakage from the last British underground test, and that he will therefore continue with such tests as necessary?

That seems to be rather a different question. The test which took place last September, on which I reported to the House—and which was a repeat of a test that failed a year earlier, under the previous Government—was not of the kind that would involve venting. It was a test for economy purposes which had failed a year earlier, at great cost. We repeated it and succeeded with it.
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[Interruption.] I hope that the House regards this question as a serious matter and not merely one for the giggling that we had in the last Parliament on these questions. In answer to the right hon. Gentleman, if it became necessary, for similar reasons, to have a further test, we would have one, but we succeeded in that test, so it is not necessary to repeat it a second time.

Has the right hon. Gentleman noticed the welcome news of a gradual decrease of strontium in human bones as a result of the partial Test Ban Treaty? Will he take note of the general satisfaction about the value of that treaty to the entire human race?

I think that all of us have noticed with satisfaction the progressively successful results of that treaty in terms of the index mentioned by the right hon. and learned Gentleman. That treaty was widely welcomed, not only in this country but throughout the world.

The following is the information:On 25th April, 1966, a low yield underground nuclear test in Nevada accidentally released a small amount of radio-activity into the atmosphere, though the highest radiation level recorded in the immediate vicinity of the test was, I understand, many times less than that caused by ordinary medical X-ray treatment. Neither this test nor any other United States underground test has caused radio-active debris to be present outside the territorial limits of the United States. No danger to the health of people within the United States resulted and there was no possible danger to other peoples of the world.Her Majesty's Government's policy in relation to continued nuclear testing of all kinds by all countries is to press forward as quickly as possible with the negotiation of a comprehensive test ban treaty.